[UPSTREAM] Attempt at improving ADC access

Balaji Rao balajirrao at openmoko.org
Thu Oct 16 09:37:16 CEST 2008


On Thu, Oct 16, 2008 at 12:18:50AM +0100, Andy Green wrote:
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> Somebody in the thread at some point said:
>
> | Also, don't the queue head/tail manipulation functions require locking ?
>
> When I wrote them I recall coming to the idea that no locking is needed
> because each of the "threads" only controls the head or the tail
> exclusively.
>

Hmm.. I don't understand. Since the queue update statement is not
atomic, it could be preempted anywhere 'in between' by an interrupt
handler which might also want to add to the queue. This can lead
to problems. Isn't it? Is there any reason why this can't happen ?
Please explain.

	- Balaji




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